The purpose of the preliminary swings is not only to give the hammer some initial speed before going into the turns , but also to set the implement on the right path . So the first points are : how many and how fast the swings ?  , thinking at finding the OPTIMAL speed for each individual athlete . Then to try to achieve the largest possible circle and range of motion to gain as much momentum as possible . Doing this there are many individual ways to achieve these swings depending the character of the athlete and his technical level. You can copy one champion or another (Some are doing the step in which consists in starting in a side oriented position and move the right foot forward to the parallel feet stance before going into the entry) but you have to take care to what belongs to ”style” and what can ”eventually” bring some technical improvement . The guideline is always : ”Be comfortable , well balanced , with a great posture and with the arms and shoulders as relaxed as possible”.